Portable pulling device

ABSTRACT

A highly portable pulling device for moving loads along a cable. The device includes a capstan around which the cable is wound for at least one turn and a gasoline engine for driving the capstan. It is housed in an ellipsoidal housing having a generally smooth outer contour to prevent snagging when the device is used in close proximity to trees, bushes, and the like.

Unite States Patent Rohrer et al.

[ 5] Man-14,1972

[54] PORTABLE PULLING DEVICE [72] Inventors: Daniel Rohrer, Route 1, Box 207C, Hillsboro, Oreg. 97123; Paul W. Hait, 12872 Ashley Court, Saratoga, Calif. 95070 [221 Filed: July 14, 1969 [21] Appl.No.: 841,434

[52] U.S. Cl ..254/150, 123/136, 254/161 [51] Int. Cl. ..B66d 3/00, B66d 1/30 [58] FieldofSearch ..254/150,175.7,175.5,161; 64/28; 123/136 [56] References Cited UNITED STATES PATENTS 1,243,292 10/1917 Hochon et al. ..254/150 2,465,604 3/1949 Potter Allenbaugh..

Guffey ..64/28 3,170,005 2/1965 Phillips 1 23/136 3,227,420 1/1966 Scott ....254/175.7 1,990,163 2/1935 Blackburn ..254/l6l 2,559,450 7/1951 Mayer ..254/l61 FOREIGN PATENTS OR APPLICATIONS 1,407,573 0/1965 France ..254/l 75.5

Primary Examiner-Harvey C. Homsby Assistant ExaminerMerle F. Maffei Attorney-Flehr, Hohbach, Test, Albn'tton & Herbert [57] ABSTRACT A highly portable pulling device for moving loads along a cable, The device includes a capstan around which the cable is wound for at least one turn and a gasoline engine for driving the capstan. It is housed in an ellipsoidal housing having a generally smooth outer contour to prevent snagging when the device is used in close proximity to trees, bushes, and the like.

15 Claims, 6 Drawing Figures PMENTEBMAR 14 1972 3.648 977 sum 1 [1F 3 INVENTORS Dame! E Rohrer BY w W M Attorneys PATENTEDMAR 14 I972 SHEET 3 0F 3 INVENTORS Daniel E Rohrer Paul W Hair 9;] 79 orneys PORTABLE PULLING DEVICE BACKGROUND OF THE INVENTION This invention pertains generally to pulling and lifting machines and more particularly to a small portable lifting device which is particularly suitable for use by hunters and other sportsmen.

Hunters and sportsmen frequently travel into remote areas in which transportation of cumbersome loads over the rugged terrain can be a burdensome problem. For example, deer and elk hunters may find large animals in deep canyons and ravines. Packing animals weighing on the order of 200 pounds up the steep walls of such canyons and ravines is a tiresome and time consuming task.

I-Ieretofore, some hunters have attempted to use devices such as conventional power saw winches for pulling their game up steep slopes. These winches generally include a gasoline engine which drives a drum upon which a fixed amount of cable is wound. These devices typically weigh on the order of 100 pounds and are themselves cumbersome to transport. They are generally used by securing the winch to a fixed object uphill from the load to be lifted and pulling the load up to the winch by winding the cable around the drum. With this winch type of device, the distance traversed in each pull is limited by the amount of cable that can be wound on the drum, and the winch itself must be carried up the hill.

There is therefore a need for a new and improved portable pulling device suitable for use by hunters and other sportsmen.

SUMMARY AND OBJECTS OF THE INVENTION The present invention provides a small and compact pulling device which can be readily carried by a person. The device includes a capstan driven by a small gasoline engine for propelling the device and load attached thereto along a cable. With this device, the length of the cable is not limited by the size of the capstan, nor is it necessary to carry the device itself up the hill. The device is housed in a shell having a substantially smooth outer contour to prevent it from being snagged by trees, bushes, and the like.

It is in general an object of the invention to provide a small and compact pulling unit which can be readily carried by a person and which is particularly suitable for use by hunters and sportsmen.

Another object of the invention is to provide a pulling device of the above character which includes a gasoline engine and capstan drive.

Another object of the invention is to provide a pulling device of the above character which includes means for automatically disconnecting the load from the power source when the load exceeds a predetermined limit.

Another object of the invention is to provide a pulling device of the above character having a substantially smooth outer contour that is not easily snagged by trees, bushes, and the like.

Another object of the invention is to provide a pulling device of the above character having a substantially smooth outer contour that is not easily snagged by trees, bushes, and the like.

Another object of the invention is to provide a pulling device of the above character which is capable of operating in any position.

Additional objects and features of the invention will be apparent from the following description in which the preferred embodiment is set forth in detail in conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a top view of one embodiment of a pulling device incorporating the present invention.

FIG. 2 is a bottom view of the embodiment shown in FIG. 1.

FIG. 3 is a cross-sectional view of the embodiment shown in FIGS. 1 and 2.

FIG. 4 illustrates how one embodiment of the invention may be used to pull a boat up an embankment.

FIG. 5 illustrates how the embodiment may be used ro raise an object up a steep cliff.

FIG. 6 illustrates the embodiment used to p'ull a deer up a hill.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the preferred embodiment, the pulling device comprises generally a frame'll, a capstan l2 rotatably mounted on the frame, driving means l3 mounted on the frame and operably connected to the capstan, a cable 14, hook means 16 for attaching loads to the device, and a outer shell 17.

The frame 11 is a relatively thin member having a generally elliptical outer contour. The frame includes a central portion 21 which, as described hereinafter in detail, is adapted for mounting the capstan and driving means. A flange portion 22 having a generally triangular cross-section extends around the outer periphery of the frame, and a web portion 23 extends between the central portion 21 and theouter flange 22. As will appear hereinafter, the frame 11 provides a means for mounting all of the elements of the pulling device, and the flange 22 forms a portion of the outer casing of the device. The frame is conveniently fabricated of a relatively light'material such as aluminum and by a conventional process such as casting.

The driving means 13 includes a gasoline engine 26 and a transmission designated generally by the reference numeral 27. The engine is a conventional four cycle, reciprocating piston engine of compact design. It includes a mounting flange 28 which is secured to the frame 11 by bolts. Alternatively, another type of engine or an electric motor can be used for driving the unit.

The transmission 27 includes an input shaft 31, a lay shaft 32, and an output shaft 33. Each of theseshafts is rotatably mounted in bearings 34 disposed in bearing, bores in the central portion 21 of the frame 11. The input shaft 31 is connected directly to the crank shaft of the engine 26, and in the preferred embodiment it is simply'an extension of the crank shaft. A first pinion 36 is mounted on the input shaft 31 and adapted for rotation therewith. This pinion engages and drives a first spur gear 37 which is mounted on the lay shaft 32. A second pinion 38 is mounted on the lay shaft Y32 and adapted for rotation with the spur gear 371The pinion 38 engages and drives a second spur gear 39 which is mounted on the output shaft 33. The capstan 12 is also mounted on the output shaft 33 and adapted for rotation with the spur gear 39. The capstan and gears 36-39 are fixed to the shafts by conventional means such as set screws.

The central portion 21 of the frame 11 is formed to provide a housing for the transmission 27. A recess 41 is provided in the upper surface of the frame, and a recess 42 is provided in the lower surface. The gear trains 36-37 and 3&39 are disposed in these recesses. The upper recess is closed by a cover plate 43 which is secured to the frame by means of screws 44. The lower recess is likewise closed by a cover plate 46 secured to the frame by screws 47. If desired, the cover plates 43 and 46 can be made identical to each other so that they will be interchangeable. Each of the cover plates is bored to receive two of the bearings34 in which the transmission shafts are mounted. Bore holes are likewise provided in the frame to accommodate the shafts 31-33. The cavity defined by the recesses and bore holes can be filled with a lubricant and sealed to prevent leakage of the lubricant. Suitable sealing means includes gaskets between each of the cover plates and frame and dynamic seals around the input and output shafts.

The cable 14 can be any flexible cable which is relatively light in weight, yet is strong enough to support the loads which will be pulled by the device. In the preferred embodiment, a rope fabricated of nylon is used. As indicated at 49, the cable 14 is wound around the capstan 12. While the exact number of turns is not critical, there should be enough turns to insure proper engagement between the cable and the capstan. Accordingly, it is preferable that the cable make at least one full turn around the capstan. In FIG. 3, the cable is shown approaching the capstan from thefrontSl of the pulling device and exiting toward the rear 52. It is not, however, necessary that the directions of approach and exit be opposed to each other.

Means is provided for guiding the cable to and from the capstan. In the preferred embodiment, this means includes a plurality of pigtails 53 which are mounted to the flange portion 22 of the frame 11. These pigtails prevent the cable from walking off the capstan and from rubbing against the housing 17.

The hook means 16 is secured to the frame 11 at the rear end 52 of the pulling unit. This hook provides means for attaching loads to the pulling device and can be a simple hook as illustrated. Alternatively, if desired, a different type of connector such as an eyelet can be utilized.

Release means is provided for automatically disconnecting the driving power from the hook means to prevent damage to the pulling unit due to overloads. In the preferred embodiment, this means includes a pair of shear pins 54 mounting the hook 16 to the frame. These shear pins are adapted to rupture whenever the force exerted on the hook means exceeds a predetermined limit. Alternatively, the capstan 12 or any element in the drive train could be mounted by means of a shear pin.

The outer shell 17 is generally ellipsoidal in shape and encloses the frame 11 and driving means 13. Because of the ellipsoidal shape, the device is able to guide itself around obstacles such as trees, rocks, and ledges. The shell is formed in two sections, an upper section 56 and the lower section 57, each of which is removably secured to the flange portion 22 of the frame 11 by means of a plurality of peripherally spaced screws 58. In the preferred embodiment, the outer shell is fabricated of a high impact plastic such as polycarbonate plastic or polypropylene.

The upper shell section 56 is formed to include a depressed cylindrical region 59, in which the capstan 12 is disposed, and a plurality of depressed passageways 61-64 extending from the region 59 to the outer extremities of the frame 11. Each of the passageways includes a pair of substantially planar and parallel side walls, such as 63a, and an arcuately curved bottom portion, such as 63b, joining the side walls. As can best be seen in FIG. 3, the bottom portions lie in close proximity to the upper extremity of the frame 11. One of the pigtails 53 is disposed at the outer extremity of each of the passageways, and the side walls of each passageway are preferably separated by a distance substantially greater than the diameter of the cable 14 so that the cable can pass through each passageway from the capstan to the pigtail without rubbing against the sidewalls.

The upper shell section 56 is also formed to include a storage compartment and a fuel tank. The storage compartment, designated generally by the reference numeral 66, is located in the region bounded by the passageways 62 and 63 and the outer periphery of the frame 11. The compartment includes a hinged cover 67 having a contour corresponding to the contour of the remainder of the shell and mounted thereto by means of hinges 68. Latching means for holding the cover 68 in its closed position is provided in a recess 69. The compartment 66 has been found to be particularly convenient for storing ropes and cables associated with the pulling unit.

The fuel tank, designated generally by the reference numeral 7], lies in the region bounded by the passageways 62 and 64 and the outer periphery of the frame 11. A filler cap 72 is provided in a recessed area 73 formed in the shell. In the preferred embodiment, the fuel tank includes a liner 74 fabricated of a light weight material which is impervious to gasoline. If desired, the liner can be omitted if the shell is selffabricated of a gasoline impervious material.

The lower shell section 57 provides a cover for the engine 26. This section is formed to include a plurality of holes 76 in the vicinity of the engine. These holes provide means for ventilating the engine and also for supplying air to the carburetor. The lower shell section is also formed to include recessed areas 77 and 78. A knob 79 is disposed in the recessed area 77 and connected to the engines conventional starting rope 81 to provide means of starting the engine without removing the shell section. A muffler 82 is disposed in the recessed area 78 and is connected to the engine by an exhaust pipe 83. In the preferred embodiment, the muffler 82 is packed with a ceramic fiber to prevent sparks and other hot particles from being discharged from the engines exhaust system. If desired, other controls such as a throttle and choke can be extended through the shell and housed in additional recessed areas.

It is to be noted that the outer contour of the ellipsoidal shell is substantially smooth and free of protrusions. This enables the pulling device to be operated in close proximity to trees, bushes, and other objects without danger of being snagged thereby.

The engine used in the preferred embodiment is capable of operating in any position, and means is provided for delivering fuel to the engine regardless of the attitude of the pulling device. This means includes a fuel pump 84 mounted on the engine, a fuel line 86 extending from the fuel pump and into the fuel tank 71, and a porous ball 87 mounted on the intake end of the fuel line inside the tank. The portion of the fuel line inside the tank is flexible and is of sufficient length to permit the ball to reach the lowest point in the tank regardless of the position of the pulling device. The ball is fabricated of a material through which gasoline can pass freely and which has a higher specific gravity than gasoline. Thus, the ball is attracted by gravity by the lowest point in the tank.

Operation of the pulling device can now be described briefly as follows. Let it be assumed that a load to be pulled has been attached to the hook means 16 by suitable means such as a rope. The cable 14 is fed through the pigtail 53 at the forward end 51 of the pulling unit, wrapped around the capstan for at least one turn, and fed out through another pigtail 53. The end 14a of the rope extending from the forward end of the pulling device is attached to a fixed object, such as a tree. The engine is started, causing the capstan to be driven through the gears 36-39. As long as no tension is applied to the free end 14b of the cable, the capstan rotates freely within the portion of the cable wound thereabout. Pulling on the free end of the cable causes frictional engagement between the capstan and the cable, thereby causing the pulling device and load attached thereto to advance along the cable toward the fixed object. In FIG. 3, the free end 14b of the cable is illustrated as passing through passageway 62. However, if desired, it can be brought out through either of the other passageways 63 or 64.

FIG. 4 illustrates the pulling device 10 being used to draw a boat 88 up an embankment. The boat is attached to the pulling device by means of a rope 89, and the end 14a of the cable is attached to a boat trailer 91. Movement of the pulling device and the boat is controlled by the free end 14b of the cable.

In FIG. 5, the device is being used to lift a package 92 up a did. The package is attached to the pulling unit by means of a sling 93, and the end 14a of the cable is secured to a tree 94.

FIG. 6 illustrates the pulling device 10 being used to pull a deer 96 up a slope. The deer is attached to the pulling unit by means of a rope 89 tied to the hook means 16, and the end of the cable is secured to a stump 97.

In FIGS. 4-6, it will be noted that the man manipulating the free end of the cable 140 is standing uphill from the pulling device and load. This is possible even though the fixed and free ends of the cable leaves the pulling device in different directions because of the guiding action provided by the pig tails. Also, the pull required on the free end of the cable to produce frictional engagement between the cable and capstan is not very great.

One pulling device has been constructed according to the present invention utilizing an engine rated at one horsepower for a shaft speed of 6,000 rpm. With a transmission gear ratio on the order of 50:1, this device is capable of pulling loads on the order of 500 pounds. The device itself weighs less than 15 pounds and is of a sufi'iciently small size that it is readily carried by a person. It is most conveniently carried in a back pack, but if desired, it can be suspended from the carriers built.

It is apparent from the foregoing that a new and improved portable pulling unit has been provided. This device is particularly suitable for use by hunters and other sportsmen. While only a presently preferred embodiment has been described herein, it will be apparent to those familiar with the art that certain changes and modifications can be made without departing from the scope of the invention as defined by the following claims.

We claim:

1. In a small portable pulling device adapted for movement along a cable, a frame, a capstan rotatably mounted on said frame at a location generally central of said frame, driving means mounted on said frame and operably connected to said capstan for continuously rotating said capstan during the operation of the device a cable wound for at least one turn on said capstan, said cable having a first end adapted to be secured to a first object and a second end providing means for tensioning said cable to draw said cable into frictional engagement with the rotating capstan to cause the device to travel along said cable toward said first end and said first object, said capstan rotating freely relative to said cable when said cable is not drawn into engagement therewith, hook means secured to said frame and adapted for connection to a second object, and a generally ellipsoidal shell enclosing said frame and driving means, said shell having a substantially smooth outer contour without external protrusions, whereby said pulling device is adapted for movement in close proximity to foreign objects without danger of being snagged thereby, the outer contour of said shell being formed to include a generally cylindrical depressed region in which said capstan is mounted, said depressed region having a depth at least as great as the height of said capstan, said outer contour also being formed to include at least one recessed passageway through which said cable passes extending generally tangentially from the cylindrical depressed region and having a depth corresponding to the depth of said region. I

2. A pulling device as in claim 1 wherein said ellipsoidal shell is formed in two sections removably secured to said frame, one of said sections being formed to include at least one storage compartment.

3. A pulling device as in claim 2 wherein said driving means includes a fuel driven engine and one of said storage compartments is a fuel tank having a filler cap mounted in a recess formed in the outer contour of said shell.

4. A pulling device as in claim 1 together with release means intermediate said driving means and said hook means for disconnecting said driving means from said hook means when the force exerted on said hook means by an object connected thereto exceeds a predetermined limit.

5. A pulling device as in claim 4 wherein said release means comprises at least one shear pin securing said hook means to said frame, said shear pin being adapted for rupturing when the force exerted on said hook means exceeds the predetermined limit.

6. A pulling device as in claim 1 wherein said driving means includes a gasoline engine and a transmission mounted on said frame, said transmission being connected intermediate said engine and said capstan for delivering driving power from said engine to said capstan.

7. A pulling device as in claim 6 wherein said transmission includes input, lay, and output shafts rotatably mounted on said frame, said input shaft being connected directly to the crankshaft of said engine and said capstan being fixed to said output shaft, a first pinion fixed to said input shaft and engaging a first spur gear fixed to said lay shaft, a second pinion fixed to said lay shaft for rotation with said first spur gear, and a second spur gear fixed to said output shaft and driven by said second pinion, whereby said capstan is driven at a slower speed than the crankshaft of said engine.

8. A pulling device as in claim 6 wherein said engine is capable of operating in any position and wherein said ellipsoidal shell is formed to include a fuel tank, together with fuel pump means connected to said engine for supplying fuel from said tank to said engine regardless of the attitude of said pulling device.

9. A pulling device as in claim 8 wherein said fuel pump means includes a fuel line extending into the interior of said fuel tank and means for submerging the intake end of said line in fuel in said tank regardless of the attitude of said pulling device.

10. A pulling device as in claim 9 wherein said last named means includes a porous ball mounted on the intake end of said fuel line, said ball being fabricated of a material capable of passing fuel freely and having a greater specific gravity than that of the fuel.

11. A pulling device as in claim 1 wherein said driving means includes a gasoline engine on the order of one hor sepower and wherein said device weighs on the order of [5 pounds and is of a size conveniently carried by a person, thereby providing a highly portable unit suitable for pulling loads on the order of 500 pounds.

12. In a small portable pulling device adapted for drawing a load toward a fixed object, said device being of a size readily carried on the back of a human being, a body and frame assembly having a generally smooth outer contour to permit the device to move in close proximity to foreign objects without being snagged thereby, said body and frame assembly also having a wedge-shaped nose portion for guiding the device around objects such as trees and rocks, a capstan rotatably mounted in a generally central location on the frame portion of said body and frame assembly, motive means mounted on said assembly and operably connected for driving said capstan, an elongate flexible element having at least one turn wound on said capstan and having a first end adapted to be secured to the fixed object and a control end adapted to be manipulated by an operator to control the frictional engagement between said element and said capstan, and means mounted on said body and frame assembly for connecting said assembly to the load, the outer contour of said body and frame assembly being formed to include a generally cylindrical depressed region in which said capstan is mounted, said depressed region having a depth at least as great as the height of said capstan, said outer contour also being formed to include at least one recessed passageway through which the elongate flexible element passes, said passageway extending generally tangentially from the cylindrical depressed region and having a depth corresponding to the depth of said region.

13. A pulling device as in claim 12 together with automatic disconnect means for disconnecting said motive means from said connector means when the force exerted by the load connected to said connector means exceeds a predetermined limit.

14. In a portable pulling device for drawing a load along a cable toward a fixed object to which the cable is attached, said device including a frame member, means for attaching the load to said frame member in such manner that the load can be pulled by the device, driving means mounted on the frame member and engaging the cable for causing movement of the device relative to the cable the improvement comprising a generally ellipsoidal shell enclosing the frame member and driving means, said shell having a generally smooth outer contour without external protrusions, whereby the pulling device is adapted for movement in close proximity to foreign objects without danger of being snagged thereby, the outer contour of said shell being formed to include a generally cylindrical depressed region in which said capstan is mounted, said depressed region having a depth at least as great as the height of said capstan, said outer contour also being formed to include at least one recessed passageway through which said cable passes extending generally tangentially from the cylindrical depressed region and having a depth corresponding to the depth of said region.

15. A pulling device as in claim 14 wherein the means for attaching the load to the frame member includes means for disconnecting the load when the force exerted thereby exceeds a predetermined limit.

t A t n an new: 

1. In a small portable pulling device adapted for movement along a cable, a frame, a capstan rotatably mounted on said frame at a location generally central of said frame, driving means mounted on said frame and operably connected to said capstan for continuously rotating said capstan during the operation of the device, a cable wound for at least one turn on said capstan, said cable having a first end adapted to be secured to a first object and a second end providing means for tensioning said cable to draw said cable into frictional engagement with the rotating capstan to cause the device to travel along said cable toward said first end and said first object, said capstan rotating freely relative to said cable when said cable is not drawn into engagement therewith, hook means secured to said frame and adapted for connection to a second object, and a generally ellipsoidal shell enclosing said frame and driving means, said shell having a substantially smooth outer contour without external protrusions, whereby said pulling device is adapted for movement in close proximity to foreign objects without danger of being snagged thereby, the outer contour of said shell being formed to include a generally cylindrical depressed region in which said capstan is mounted, said depressed region having a depth at least as great as the height of said capstan, said outer contour also being formed to include at least one recessed passageway through which said cable passes extending generally tangentially from the cylindrical depressed region and having a depth corresponding to the depth of said region.
 2. A pulling device as in claim 1 wherein said ellipsoidal shell is formed in two sections removably secured to said framE, one of said sections being formed to include at least one storage compartment.
 3. A pulling device as in claim 2 wherein said driving means includes a fuel driven engine and one of said storage compartments is a fuel tank having a filler cap mounted in a recess formed in the outer contour of said shell.
 4. A pulling device as in claim 1 together with release means intermediate said driving means and said hook means for disconnecting said driving means from said hook means when the force exerted on said hook means by an object connected thereto exceeds a predetermined limit.
 5. A pulling device as in claim 4 wherein said release means comprises at least one shear pin securing said hook means to said frame, said shear pin being adapted for rupturing when the force exerted on said hook means exceeds the predetermined limit.
 6. A pulling device as in claim 1 wherein said driving means includes a gasoline engine and a transmission mounted on said frame, said transmission being connected intermediate said engine and said capstan for delivering driving power from said engine to said capstan.
 7. A pulling device as in claim 6 wherein said transmission includes input, lay, and output shafts rotatably mounted on said frame, said input shaft being connected directly to the crankshaft of said engine and said capstan being fixed to said output shaft, a first pinion fixed to said input shaft and engaging a first spur gear fixed to said lay shaft, a second pinion fixed to said lay shaft for rotation with said first spur gear, and a second spur gear fixed to said output shaft and driven by said second pinion, whereby said capstan is driven at a slower speed than the crankshaft of said engine.
 8. A pulling device as in claim 6 wherein said engine is capable of operating in any position and wherein said ellipsoidal shell is formed to include a fuel tank, together with fuel pump means connected to said engine for supplying fuel from said tank to said engine regardless of the attitude of said pulling device.
 9. A pulling device as in claim 8 wherein said fuel pump means includes a fuel line extending into the interior of said fuel tank and means for submerging the intake end of said line in fuel in said tank regardless of the attitude of said pulling device.
 10. A pulling device as in claim 9 wherein said last named means includes a porous ball mounted on the intake end of said fuel line, said ball being fabricated of a material capable of passing fuel freely and having a greater specific gravity than that of the fuel.
 11. A pulling device as in claim 1 wherein said driving means includes a gasoline engine on the order of one horsepower and wherein said device weighs on the order of 15 pounds and is of a size conveniently carried by a person, thereby providing a highly portable unit suitable for pulling loads on the order of 500 pounds.
 12. In a small portable pulling device adapted for drawing a load toward a fixed object, said device being of a size readily carried on the back of a human being, a body and frame assembly having a generally smooth outer contour to permit the device to move in close proximity to foreign objects without being snagged thereby, said body and frame assembly also having a wedge-shaped nose portion for guiding the device around objects such as trees and rocks, a capstan rotatably mounted in a generally central location on the frame portion of said body and frame assembly, motive means mounted on said assembly and operably connected for driving said capstan, an elogate flexible element having at least one turn wound on said capstan and having a first end adapted to be secured to the fixed object and a control end adapted to be manipulated by an operator to control the frictional engagement between said element and said capstan, and means mounted on said body and frame assembly for connecting said assembly to the load, the outer contour of said body and frame assembly being formed to include a generally cylindrical depressed Region in which said capstan is mounted, said depressed region having a depth at least as great as the height of said capstan, said outer contour also being formed to include at least one recessed passageway through which the elongate flexible element passes, said passageway extending generally tangentially from the cylindrical depressed region and having a depth corresponding to the depth of said region.
 13. A pulling device as in claim 12 together with automatic disconnect means for disconnecting said motive means from said connector means when the force exerted by the load connected to said connector means exceeds a predetermined limit.
 14. In a portable pulling device for drawing a load along a cable toward a fixed object to which the cable is attached, said device including a frame member, means for attaching the load to said frame member in such manner that the load can be pulled by the device, driving means mounted on the frame member and engaging the cable for causing movement of the device relative to the cable the improvement comprising a generally ellipsoidal shell enclosing the frame member and driving means, said shell having a generally smooth outer contour without external protrusions, whereby the pulling device is adapted for movement in close proximity to foreign objects without danger of being snagged thereby, the outer contour of said shell being formed to include a generally cylindrical depressed region in which said capstan is mounted, said depressed region having a depth at least as great as the height of said capstan, said outer contour also being formed to include at least one recessed passageway through which said cable passes extending generally tangentially from the cylindrical depressed region and having a depth corresponding to the depth of said region.
 15. A pulling device as in claim 14 wherein the means for attaching the load to the frame member includes means for disconnecting the load when the force exerted thereby exceeds a predetermined limit. 